Studies in polarography IV reduction of manganate at the dropping mercury electrode

The polarography of manganate has been studied in sodium hydroxide solutions as supporting electrolyte, particularly as regards the effects of alkalinity, manganate concentration and the presence of formic acid. At alkalinities less than 1 M NaOH reduction passes to Mn+2 and then to Mn0 along two main waves. In 1 M NaOH reduction yields Mn+3 and then Mn0. Polarograms in 0.1, 0.5 and 1 M alkali can be used for the determination of manganate in 2.5 × 10−4 to 2 × 10−3M solutions.